#intro {
	/*background: rgba(0,0,0,.7);  我修改的*/
	background: black url(img/题目背景.jpg) bottom center;
	background-size: 100% 100%;
	background-repeat:no-repeat;
	padding: 0;
	border: 0;
}

#intro h1 {
	width: 60%;
	min-height: 100px;
	margin: 5% auto 0;
}

#intro .attribution {
	font-family: Helvetica, sans-serif;
	font-weight: bold;
	text-align: center;
	font-size: 100%;
	line-height: .3;
	color: rgba(0,0,0,.7);
	text-shadow: none;
	/*background: url(img/rainbow-wood.jpg) bottom;*/
	padding:.6em 0 0;
	overflow: hidden;
}


#css-controls-demo label {
	display: block;
}

@media only screen and (-webkit-min-device-pixel-ratio:0) {
/* hack to avoid using the Object element in Safari/WebKit, due to WebKit Bug 27190 */
	/*object[type="image/svg+xml"] {
		display: none;
	}*/
	
	/*#intro h1 {
		background: url(logo.svg) no-repeat center;
		background-size:100% auto;
	}*/
}